Plain numbered sequels are becoming a little old-fashioned these days. The year 2013 will most likely be remembered for movies with names such as The Hobbit: The Desolation of Smaug or Star Trek Into Darkness and Thor: The Dark World. And yet the new Iron Man film, for which 20 minutes of footage was screened to bloggers and critics earlier this week, is titled plain old Iron Man 3. Did writer-director Shane Black, who's stepping into Jon Favreau's shoes for the new instalment, simply run out of ideas? Or – more likely – has Marvel Studios simply recognised that Robert Downey Jr's super-suited hero already has such a standing on the big screen that no adornments are necessary?

Downey Jr was unquestionably the star of the obscenely successful The Avengers, though the Hulk certainly gave him a good run for his greenbacks. With the $1.5bn (£990m) superhero ensemble having taken the genre into new territory in terms of popularity with audiences, an awful lot is riding on Iron Man 3. Tony Stark's alter ego may have been considered a second-tier figure in the comic books, but on the big screen he has a chance to soar higher than the once-unstoppable troika of Batman, Superman and Spider-Man to the top of the superhero tree.

On paper, Iron Man 3 certainly ups the stakes. With an Oscar-winner, Ben Kingsley, as villain the Mandarin, one of Stark's best-known enemies, and the addition of Guy Pearce and Rebecca Hall as Aldrich Killian and Maya Hansen, co-creators of the Extremis virus, our hero is facing an entirely new level of adversity. Marvel apparently considered using the Mandarin for the first Iron Man film but decided it was too soon to introduce such a powerful figure, an entirely sensible move. Weak antagonists have been the traditional downfall of superhero sequels from Spider-Man 3 to the later Superman movies. Even classier entries such as The Dark Knight Rises and The Amazing Spider-Man would have been better served had their makers been able to swap out Bane and the Lizard for the Joker and Green Goblin.

The footage we saw yesterday illustrated the power of the Mandarin in an extended sequence in which Stark's uber-modern California cliff-top mansion is reduced to rubble by a helicopter attack. If you think about it, Iron Man up until now has rarely been challenged by an enemy who did not have an obvious weakness, or who simply wasn't up to the task of defeating him in the first place. His problems have largely been connected to issues with suit technology or his own ill-health. Make no mistake: the Mandarin is more than capable of orchestrating chaos on a level that may be too much for one Iron Man to handle. Of course, Stark can call on the newly renamed Iron Patriot (Don Cheadle as Colonel James Rhodes) for help, but at one point during the footage we saw him aided by an entire fleet of multicoloured suits. Whether there was anyone inside them remains to be seen, but it's clear Iron Man has some decent backup despite the absence of his Avenger pals.

In fact, the series is fast turning into a superhero saga for Top Gear types. As well as all those snappy spare suits – many of which are currently being debuted via an online viral campaign – Stark is able to call on improved tech to ping his body armour on to his torso from virtually anywhere. We saw an example of this in The Avengers, but it seems likely to have been updated. Could this be the nanotech-oriented Extremis virus at play? And what are the odds that Killian and Hansen will pass up the opportunity to use their influence over Iron Man's suit technology for nefarious reasons? Might this be why we saw the body armour looming menacingly over its owner in a previous trailer?

Kingsley's Mandarin, by the way, looks like Osama bin Laden with a Manchu topknot. The original character was oriental, but it seems reasonable to accept Black's recent explanation that going down such a route would have led to inevitable stereotyping.

One sequence I initially wasn't entirely sure about saw Stark holed up a long way from home to rebuild himself after suffering a horrendous attack. Helping him out was a 12-year-old boy whose appearance initially gave the movie the air of a hokey 80s action-comedy flick, one of those in which the hero gets a cheery young sidekick in need of a father figure because some misguided Hollywood suit thought it would sell more merchandise. Luckily, this is a film starring Downey Jr from the writer and director of Kiss Kiss, Bang Bang (Black), so the poor kid just gets ordered about and told not to be – and I quote – a "pussy" when he whinges about a bully at school. It's a slick, smart save worthy of Joss Whedon himself.

Iron Man 3 arrives in the UK on 26 April and debuts in the US on 3 May. Are you expecting more Avengers-style heroics from the wisecracking superhero, or will this be the movie that brings Tony Stark and his multitude of multicoloured suits back down to Earth with a bang?